1. Field of the Invention
This invention relates to an electronic musical instrument and in particular is concerned with a metronome clock means for an automatic rhythm generator.
2. Description of the Prior Art
Automatic rhythm generators are used to create a rhythmic background pattern of sounds which are used in combination with music played by a performer on an musical instrument. Such generators are commonly incorporated as subsystems in an electronic keyboard instrument such as an organ. Automatic rhythm generators use a controllable variable speed clock to generate timing signals which control the generator logic system. This clock is called the metronome clock because it establishes the timing of the beats within a musical measure. Most automatic rhythm generators use a lamp which is illuminated at the metronome clock rate. By visually observing the blinking rate of this lamp, the musician varies a clock rate control until he establishes a desired metronome clock rate. A rhythm generator having these features is described in U.S. Pat. No. 3,763,305.
While the procedure of visually setting the metronome clock rate is easy to implement, one finds that this is not a "natural" technique for a musician. The musician does not hear any sounds from the metronome clock and the player is usually unaccustomed by training or intuition to associate a blinking lamp rate with a desired metronome rate for a selected rhythm pattern. It is not at all unusual, even in a concert environment, to find that a musician ignores the lamp and turns on the rhythm sounds so that he can hear the rhythmic pattern as he adjusts the metronome clock's speed. By training, or perhaps by some inherent instinct, musicians seem to have a tactile sense of communicating and remembering a rhythm rate. This tactile sense of communicating a metronome beat is very apparent when one notices many members of an orchestra "beating time" with their feet. They do this in spite of the fact that the conductor is furnishing a visual metronome rate via the gyrations of his baton.